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B767 was issued descent to FL340 for conflicting traffic; but when descent was initiated; TCAS RA commanded a climb; and flight crew climbed to avoid traffic.
| Attributes | |
| ACN | 740997 |
| Time | |
| Date | 200706 |
| Local Time Of Day | 1201 To 1800 |
| Place | |
| Locale Reference | airport : als.airport |
| State Reference | CO |
| Altitude | msl single value : 36000 |
| Aircraft 1 | |
| Controlling Facilities | artcc : zdv.artcc |
| Operator | common carrier : air carrier |
| Make Model Name | B767-300 and 300 ER |
| Operating Under FAR Part | Part 121 |
| Flight Phase | cruise : level |
| Flight Plan | IFR |
| Aircraft 2 | |
| Controlling Facilities | artcc : zdv.artcc |
| Operator | common carrier : air carrier |
| Make Model Name | MD-80 Series (DC-9-80) Undifferentiated or Other Model |
| Operating Under FAR Part | Part 121 |
| Flight Phase | cruise : level |
| Flight Plan | IFR |
| Person 1 | |
| Affiliation | company : air carrier |
| Function | flight crew : captain oversight : pic |
| ASRS Report | 740997 |
| Events | |
| Anomaly | conflict : airborne critical non adherence : required legal separation |
| Independent Detector | aircraft equipment : tcas other flight crewa |
| Resolutory Action | flight crew : took precautionary avoidance action |
| Miss Distance | horizontal : 12000 vertical : 400 |
| Supplementary | |
| Problem Areas | ATC Human Performance Flight Crew Human Performance |
| Primary Problem | ATC Human Performance |
Narrative:
ATC directed us to descend and maintain FL340 for conflicting traffic. Traffic ahead at FL360 and to expect climb back to FL360 when clear. We initiated a descent and almost immediately (within approximately 30 seconds) received a TCAS TA for a target at FL350 and within about 5 NM to the north. This TA was followed very quickly by an RA to climb. The first officer (PF) disengaged the autoplt and autothrottle and began a slow climb (from approximately 35400) as directed by the TCAS system. I immediately advised ATC of our climb in response to the RA. He acknowledged the call and asked us what our present altitude was. I told him it was 35800 ft and asked what altitude did he want us to maintain. He said to maintain FL340. After the RA ended the first officer resumed the descent to FL340. I estimate the traffic (an MD80) passed approximately 2 mi behind us at FL350. The remainder of the flight was normal.
Original NASA ASRS Text
Title: B767 WAS ISSUED DESCENT TO FL340 FOR CONFLICTING TFC; BUT WHEN DESCENT WAS INITIATED; TCAS RA COMMANDED A CLIMB; AND FLT CREW CLIMBED TO AVOID TFC.
Narrative: ATC DIRECTED US TO DSND AND MAINTAIN FL340 FOR CONFLICTING TFC. TFC AHEAD AT FL360 AND TO EXPECT CLB BACK TO FL360 WHEN CLR. WE INITIATED A DSCNT AND ALMOST IMMEDIATELY (WITHIN APPROX 30 SECONDS) RECEIVED A TCAS TA FOR A TARGET AT FL350 AND WITHIN ABOUT 5 NM TO THE N. THIS TA WAS FOLLOWED VERY QUICKLY BY AN RA TO CLB. THE FO (PF) DISENGAGED THE AUTOPLT AND AUTOTHROTTLE AND BEGAN A SLOW CLB (FROM APPROX 35400) AS DIRECTED BY THE TCAS SYS. I IMMEDIATELY ADVISED ATC OF OUR CLB IN RESPONSE TO THE RA. HE ACKNOWLEDGED THE CALL AND ASKED US WHAT OUR PRESENT ALT WAS. I TOLD HIM IT WAS 35800 FT AND ASKED WHAT ALT DID HE WANT US TO MAINTAIN. HE SAID TO MAINTAIN FL340. AFTER THE RA ENDED THE FO RESUMED THE DSCNT TO FL340. I ESTIMATE THE TFC (AN MD80) PASSED APPROX 2 MI BEHIND US AT FL350. THE REMAINDER OF THE FLT WAS NORMAL.
Data retrieved from NASA's ASRS site as of January 2009 and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.